Introduction to the CNS Flashcards
what is the difference between sections of axons that are myelinated vs non-myelinated?
that Na+ channels are at higher concentrations at the nodes of Ranvier
what are the 3 mechanisms for termination of NT
NT: neurotransmitter
- reuptake
- breakdown by enzymes at synapse or axon terminal
- autoreceptors on the pre-synaptic terminal that inhibit release of NT
what are the factors that play into the response of a neuron?
- type of neurotransmitter
- subtype of receptor it binds to
excitatory effects are primarily by…
what is an example?
opening cation channels leading to Na+ influx and depolarization
Glutamate
inhibitory effects generally open
give an example.
Cl- channels that hyperpolarize the postsynaptic channel
GABA & Glycine
what NT coordinates w/ a cholinergic system?
Ach
is Ach excitatory, inhibitory, or both?
BOTH
when is Ach excitatory?
when bound to nicotinic receptors
when is Ach inhibitory?
when bound to muscarinic receptors
what is there a loss of in Alzheimer’s patients?
cholingeric neurons
what types of drugs are used in those w/ Alzheimer’s disease?
Procholingeric drugs
what types of drugs are used in those w/ Parkinson’s disease?
- anticholinergic drugs
- prodopaminergic drugs
what types of drugs are used to treat Achizophrenia and other psychotic disorders?
antidopaminergic drugs
what types of drugs can be used to treat anti-depresants?
- pronoradrenergic drugs
- those that increase norepinephrine
- proseotonergic drugs that increase serotonin
what types of drugs can be used as anti-psychotics?
- antiserotonergic
- antagonists at 5-HT receptors
what types of systems have inhibitory roles that can be used to treat anxiety and insomnia?
GABAergic systems
GABA-A receptors are found
postsynaptically on target cells
GABA-B receptors are…
presynaptic auto-receptors that regulate the release of neurotransmitters
glutamatergic systems are…
stimulatory
glutamatergic systems are used for
memory storage/retention
what are the 8 drug targets in neurosensory disorders?
- synthesis of neurotransmitters
- vesicular packaging
- Calcium entry through V-gated Ca2+ channels
- postsynaptic receptor agonists/antagonists/modulators
- neurotransmitter reuptake
- neurotransmitter metabolism
- neurotransmitter releasers
- action potential generation
define Alzheimer’s Disease
progressive mental deterioration w/ memory loss and loss of control of body functions
Alzheimer’s is characterized by
plaques and tangles that form in brain tissue
why is monotherapy not effective in treating the symptoms of Alzheimer’s disease?
b/c Alzheimers involves multiple NT systems
what is the cholinergic hypothesis?
memory & learning are associated w/ the cholinergic system so as the system is malfunctioning therapy is directed at enhancing cholinergic function
procholinergic drugs are preferred methods of treatments in alzheimer patients; this is done through
- cholingeric receptor agonist
- acetylcholinesterase inhibitors
cholinergic can be either muscarinic or nicotinic
define Parkinson’s Disease?
progressive deterioration of neuromuscular system usually beginning unilaterally and leadinging to bilateral rhythmis tremors, rigidity, difficulty initiating movements and bradykinesia
unlike Alzhimer’s disease Parkinson’s is primarily the loss of function in
a single NT system
what is the though about dopamine w/ Parkinson’s treatments?
w/o dopamine Ach can have an excitatory effect antagonizing the system and becoming a beneficial treatment
what causes cells to fire w/o regulation?
malfunctioning or loss of dopaminergic neurons
what is the primary goal within the BBB?
to increase dopamine
why does dopamine itself not easily cross the BBB?
b/c of its chemical properties
dopamine not being able to cross the BBB leads to the need for a…
Dopamine precursor or prodrug
what is an example of a dopamine prodrug that is able to readily cross the BBB where dopamine would be inhibited?
L-Dopa
carbidopa inhibits the peripheral metabolism of ________ to ________ by ____________. this increases the amount of ____________ in the brain
- L-Dopa
- Dopamine
- AADC
- L-Dopa/Dopamine
